US7525269B2 - Method and apparatus for sensorless position control of a permanent magnet synchronous motor (PMSM) drive system - Google Patents

Method and apparatus for sensorless position control of a permanent magnet synchronous motor (PMSM) drive system Download PDF

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US7525269B2
US7525269B2 US11/300,525 US30052505A US7525269B2 US 7525269 B2 US7525269 B2 US 7525269B2 US 30052505 A US30052505 A US 30052505A US 7525269 B2 US7525269 B2 US 7525269B2
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US20070132415A1 (en
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Nitinkumar R. Patel
Bon-Ho Bae
James M. Nagashima
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GM Global Technology Operations LLC
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Priority to PCT/US2006/061965 priority patent/WO2007070814A2/en
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/24—Vector control not involving the use of rotor position or rotor speed sensors
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
    • H02P25/022—Synchronous motors
    • H02P25/03—Synchronous motors with brushless excitation

Definitions

  • the present invention generally relates to control systems and power inverter modules, and, more particularly, to control systems, methods and apparatus for control of a PMSM drive system.
  • An electric traction drive system typically includes a power inverter module (PIM) and an AC motor.
  • PIM power inverter module
  • IPMSM Interior Permanent Magnet Synchronous Motor
  • Synchronous Reluctance Motor Synchronous Reluctance Motor
  • Switched Reluctance Motor machine types which inherently have magnetically salient rotors.
  • Other methods of detecting rotor angular position include high frequency signal injection and modified PWM test pulse excitation.
  • a balanced high frequency test signal such as a voltage or current signal
  • stator winding of an inherently salient machine can be injected on a stator winding of an inherently salient machine and the resultant effect of the balanced high frequency test signal on stator current can be measured.
  • the effect of the balanced high frequency test signal injection can be observed in a measured stator current which takes the form of amplitude modulation at two times the fundamental frequency rate. This effect is due to the spatial modulation of the magnetic saliency as the rotor rotates.
  • This method works quite well when the machine under test has inherent saliency, such as an Interior Permanent Magnet type machine.
  • SMPM Surface Mount Permanent Magnet
  • modified PWM test pulses can be used to excite the high frequency impedance of the machine.
  • the current control is ignored for the test period.
  • This can be a good method for an industrial drive.
  • a traction machine has low inductance and not controlling current during test period may result in an uncontrolled condition.
  • This technique retrieves the position information from sensed stator current which must be sampled immediately after injecting the test pulses. This increases number of times the stator current is being sampled.
  • the resultant effect of modified PWM test pulses on leakage inductances can be measured via a measured phase to neutral voltage of an induction machine.
  • This technique utilizes the property of a squirrel cage type rotor construction in an induction machine.
  • the “mechanical” saliency induced due to the rotor bars of the induction machine can be utilized.
  • a saliency image rotates as the rotor rotates and this information can be used to deduce rotor position information.
  • SMPMM Surface Mount Permanent Magnet Motor
  • a high performance permanent magnet (“PM”) machine drive system requires an absolute position sensor which is an expensive component. Moreover, the circuitry required to process its signals can also be expensive. It would be desirable to eliminate this position sensor. It would also be desirable to eliminate mechanical interface hardware, reduce cost and weight, reduce cost and weight and improve the reliability of an electric traction drive system.
  • FIG. 1 is a diagram of a simple 2-pole SMPMM showing a configuration of stator windings a, b, c and a PM;
  • FIG. 2 is a diagram which illustrates switching vectors and switching status of switches of a 2-level 3-phase inverter having eight available switching vectors;
  • FIG. 3 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 1 shown in FIG. 2 ;
  • FIG. 4 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 2 shown in FIG. 2 ;
  • FIG. 5 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 3 shown in FIG. 2 ;
  • FIG. 6 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 4 shown in FIG. 2 ;
  • FIG. 7 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 5 shown in FIG. 2 ;
  • FIG. 8 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 6 shown in FIG. 2 ;
  • FIG. 9 is a graph showing zero sequence voltages (V A — sn , V B — sn and V C — sn ) with respect to rotor angle which illustrates inductance inequality of the zero sequence voltages (V A — sn , V B — sn , and V C — sn );
  • FIG. 10 is a graph showing a trace of vector (Vsn) which represents zero sequence voltages (V A — sn , V B — sn and V C — sn ) transformed to d- and q-axis stationary reference frame with an Alpha component and a Beta component of the zero sequence voltages plotted in x-y coordinates;
  • FIG. 11 is a graph showing the phase of the vector (Vsn) represented by ⁇ EstRaw (Flux angle) in FIG. 10 ;
  • FIG. 12 is a block diagram of a control system which implements a sensorless algorithm using control hardware and 50 kW axial flux SMPMM;
  • FIG. 13 is a graph showing injecting vectors (Sia, Sib and Sic) for zero sequence voltage measurement
  • FIG. 14 is a graph showing a normal Space Vector PWM (SVPWM) waveform for current control with switching states (Sa, Sb and Sc) for phases A, B and C, respectively;
  • SVPWM Space Vector PWM
  • FIG. 15 is a graph showing a synthesized PWM waveform with modified switching vectors (Sa*, Sb* and Sc*) used to switch IGBT switches in PWM inverter to generate three phase sinusoidal voltage commands;
  • FIG. 16 is a graph showing three phase saturation induced (zero sequence voltage) signals at no load condition when no load torque is applied;
  • FIG. 17 is a graph showing three phase saturation induced (zero sequence voltage) signals at a 40% load condition when no load torque is applied;
  • FIG. 18 is a graph showing measured and estimated rotor position angles with two phase saturation induced signals at no load condition when no load torque is applied.
  • FIG. 19 is a graph showing measured and estimated rotor position angles with two phase saturation induced signals at full load condition when 100% load torque is applied.
  • Embodiments of the present invention provide methods and apparatus that allow for generating of zero-sequence voltages based on voltage commands and a motor output signal.
  • stator flux information can be determined.
  • the stator flux of the permanent magnet synchronous motor is represented in a stationary reference frame by equation (1), where ⁇ ds s , ⁇ qs s are d-axis and q-axis stator flux linkage, respectively, ⁇ PM is the stator flux linkage of the permanent magnet, i ds s , i qs s are the d-axis and q-axis stator current, and ⁇ r is the rotor angle.
  • ⁇ ds s L d i ds s + ⁇ PM cos( ⁇ r ) (1)
  • ⁇ qs s L q i qs s + ⁇ PM sin( ⁇ r ) (2)
  • stator current and inductances are known, the rotor-oriented component of the stator flux can be derived among the total stator flux, and then the rotor flux angle can be calculated.
  • FIG. 1 is a diagram of a simple 2-pole SMPMM in a showing a configuration of stator windings a, b, c and a PM.
  • FIG. 1 describes the relation between the stator inductance variation and the zero sequence voltage which is the sum of the phase to neutral voltages of phase A, B and C of the motor.
  • the 2 pole machine is used for the analysis, however, it should be appreciated that a similar analysis would apply to higher pole machines.
  • stator inductance in the motor depends on the flux distribution of the PM and the electromagnetic design magnetic design.
  • stator inductances (l a , l b , l c ) of phase a, b, and c can be described below in equations (3)-(5).
  • L s0 is the average stator inductance
  • l ⁇ is the coefficient of stator inductance variance
  • f ( ⁇ r ) is a periodic function with period of ⁇ .
  • this embodiment utilizes the zero sequence voltage components.
  • the zero sequence voltage component is zero.
  • the inductances are not equivalent, it has a value according to the configuration of the inverter switches. This condition may occur due to the main flux saturation.
  • the main flux is composed of the stator and the rotor PM flux.
  • FIG. 2 is a diagram which illustrates switching vectors and switching status of switches of a 2-level 3-phase inverter having eight available switching vectors (V 0 . . . V 7 ).
  • the zero sequence voltage is dependent on both the inductance variance and the inverter configuration due to switching status. Therefore by investigating the zero sequence voltage profile at each switching status, the appropriate combination can be derived to produce unbalanced three phase inductances at every switching instance.
  • FIGS. 3-8 are circuit diagrams which represent possible three phase stator winding configurations of stator windings with respect to the switching vectors shown in FIG. 2 .
  • FIG. 3 is a circuit diagram m which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 1 shown in FIG. 2 .
  • a voltage (Vdc) exists between node a and node bc
  • an inductance (l a ) is coupled between node a and node n
  • an inductance (l b ) is coupled between node n and node b
  • an inductance (l c ) is coupled between node n and node c.
  • FIG. 4 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 2 shown in FIG. 2 .
  • a voltage (Vdc) exists between node ab and node c
  • an inductance (l a ) is coupled between node a and node n
  • an inductance (l b ) is coupled between node n and node b
  • an inductance (l c ) is coupled between node n and node c.
  • FIG. 5 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 3 shown in FIG. 2 .
  • a voltage (Vdc) exists between node b and node ac
  • an inductance (l b ) is coupled between node b and node n
  • an inductance (l a ) is coupled between node n and node a
  • an inductance (l c ) is coupled between node n and node c.
  • FIG. 6 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 4 shown in FIG. 2 .
  • a voltage (Vdc) exists between node bc and node a
  • an inductance (l a ) is coupled between node n and node a
  • an inductance (l b ) is coupled between node n and node b
  • an inductance (l c ) is coupled between node n and node c.
  • FIG. 7 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 5 shown in FIG. 2 .
  • a voltage (Vdc) exists between node c and node ab
  • an inductance (l c ) is coupled between node c and node n
  • an inductance (l a ) is coupled between node n and node a
  • an inductance (l b ) is coupled between node n and node b.
  • FIG. 8 is a circuit diagram which represents a three phase stator winding configuration of stator windings with respect to the switching vector V 6 shown in FIG. 2 .
  • a voltage (Vdc) exists between node ac and node b
  • an inductance (l a ) is coupled between node a and node n
  • an inductance (l b ) is coupled between node n and node b
  • an inductance (l c ) is coupled between node n and node c.
  • V an l a l a + l b
  • Equations (12) through (16) show that the zero sequence voltage V sn — v4 , V sn — v6 and V sn — v2 are the same as V sn — v1 , V sn — v2 and V sn — v3 except for the sign or phase.
  • FIG. 9 is a graph showing zero sequence voltages (V A — sn , V B — sn and V C — sn ) with respect to rotor angle which illustrates inductance inequality of the zero sequence voltages (V A — sn , V B — sn and V C — sn ).
  • V A — sn , V B — sn and V C — sn the sum of the three phase-to-neutral voltages is shown as a function of rotor angle.
  • the voltage V A — sn is the sum of the three phase-to-neutral voltages resulting due to the voltage vector V 1 .
  • the voltages V B — sn and V C — sn are the sums of three phase-to-neutral voltages resulting from the voltage vectors V 3 and V 5 , respectively.
  • FIG. 9 shows that the small change (i.e. 10%) in the stator inductance produces a strong voltage signal ( ⁇ 30V).
  • the zero sequence voltage is directly related to the inductance variance, which is caused by the stator saturation.
  • the zero sequence voltages (V A — sn , V B — sn and V C — sn ) are spatially separated by 120° and are of twice the rotor fundamental frequency.
  • FIG. 10 is a graph showing a trace of vector (Vsn) which represents zero sequence voltages (V A — sn , V B — sn and V C — sn ) transformed to d- and q-axis stationary reference frame with an Alpha component and a Beta component of the zero sequence voltages plotted in x-y coordinates.
  • Vsn vector
  • V A — sn , V B — sn and V C — sn the transformation as shown in equation (17).
  • the Alpha and Beta component of the zero sequence voltages are plotted in x-y coordinate in FIG. 10 .
  • the traces periodically rotate along the circle with small distortion.
  • V alpha ⁇ ⁇ _ ⁇ ⁇ sn V beta ⁇ ⁇ _ ⁇ ⁇ sn ] 2 3 ⁇ [ 1 ⁇ - 1 2 ⁇ - 1 2 _ 0 ⁇ ⁇ 3 2 ⁇ - 3 2 ] ⁇ [ V A ⁇ ⁇ _ ⁇ ⁇ sn V B ⁇ ⁇ _ ⁇ ⁇ sn V C ⁇ ⁇ _ ⁇ ⁇ sn ] ( 17 )
  • FIG. 11 is a graph showing the phase of the vector (Vsn) represented by flux angle ( ⁇ EstRaw ) in FIG. 10 .
  • the flux angle ( ⁇ EstRaw ) is shown as a function of rotor angle.
  • the flux angle ( ⁇ EstRaw ) is shown in equation (18).
  • ⁇ EstRaw ⁇ tan 2( V Beta — sn ,V Alpha — sn ) (18)
  • the frequency is twice that of the rotor angle and the phase is synchronized with the rotor angle.
  • the rotor angle can be derived using digital signal processing of the phase information. The result shows that the rotor angle can be estimated by measuring the three zero sequence voltages (V A — sn , V B — sn and V C — sn ) one-by-one, while the voltage vectors V 1 , V 2 and V 3 are injected.
  • FIG. 12 is a block diagram of a control system which implements a sensorless algorithm using control hardware and an axial flux SMPMM.
  • the same method is also valid for the general 3-phase synchronous motor, such as Brushless DC Motor (BLDC), Interior Permanent Magnet Synchronous Motor (IPMSM) and Reluctance Motors.
  • BLDC Brushless DC Motor
  • IPMSM Interior Permanent Magnet Synchronous Motor
  • Reluctance Motors Reluctance Motors.
  • the control system comprises a stator current converter 100 , a motor 200 , a voltage generator module 220 , and an output module 240 .
  • the stator current converter 100 can receive a torque command (T*e) and generate three-phase sinusoidal voltage commands (Vap . . . Vcp).
  • the motor 200 can receive the three-phase sinusoidal voltage commands (Vap . . . Vcp) and generate the motor output (Vn).
  • the voltage generator module 220 can receive the three-phase sinusoidal voltage commands (Vap . . . Vcp) and the motor output (Vn) and generate sampled three-phase zero-sequence voltages (VA_sn . . . VC_sn).
  • the output module 240 can receive sampled three-phase zero-sequence voltages (VA_sn . . . VC_sn) and generate the final estimated rotor position angle ( ⁇ r_est).
  • components or modules which may be used to implement such a control system comprise a current mapping module ( 1 ), summer junctions ( 2 ) and ( 3 ), a current controller module ( 4 ), a synchronous-to-stationary conversion module ( 5 ), a Space Vector PWM module ( 6 ), a multiplexer module ( 7 ), a PWM inverter ( 8 ), a stationary-to-synchronous conversion module ( 9 ), an injection vector generator module ( 10 ), a 3-phase permanent magnet synchronous motor ( 11 ), a phase-neutral voltage calculator module ( 12 ), a summing junction ( 13 ), a zero sequence voltage sampling module ( 14 ), a three phase-to-two phase conversion module ( 15 ), an angle calculator module ( 16 ), a divider module ( 17 ), and an angle calibrator module ( 18 ).
  • the stator current converter 100 comprises a torque-to-current mapping module ( 1 ), a current-controller module ( 4 ), a synchronous-to-stationary conversion module ( 5 ), a space-vector PWM module ( 6 ), an injection vector generator, a multiplexer ( 7 ), a PWM inverter ( 8 ), a stationary-to-synchronous conversion module ( 9 ), and a ( 10 ).
  • the torque-to-current mapping module ( 1 ) can receive the torque command (T*e) and generate the d-axis current command (Idse*) and the q-axis current command (Iqse*).
  • the current-controller module ( 4 ) can receive the d-axis current error and the q-axis current error and generate the d-axis voltage command (Vdse*) and the q-axis voltage command (Vqse*), wherein the d-axis current error and the q-axis current error comprises a combination of the d-axis current command (Idse*) and the q-axis current command (Iqse*) and the synchronous reference frame currents (Iqse, Idse).
  • the synchronous-to-stationary conversion module ( 5 ) can receive the d-axis voltage command (Vdse*) and the q-axis voltage command (Vqse*) and the final estimated rotor position angle ( ⁇ r_est) and generate the three-phase sinusoidal voltage commands (Va* . . . Vc*).
  • the space-vector PWM module ( 6 ) can receive the three-phase sinusoidal voltage commands (Va* . . . Vc*) and generate switching vectors (Sa . . . Sc).
  • the injection vector generator ( 10 ) can generate injection vectors (Sia . . . Sic).
  • the multiplexer ( 7 ) can receive switching vectors (Sa . . . Sc) and injection vectors (Sia . . . Sic) and generate modified switching vectors (Sa′ . . . Sc′).
  • the PWM inverter ( 8 ) can receive modified switching vectors (Sa′ . . . Sc′) and generate the three-phase sinusoidal voltage commands (Vap . . . Vcp) which can be converted to resultant stator currents (Ias . . . Ics).
  • the stationary-to-synchronous conversion module ( 9 ) can receive resultant stator currents (Ias . . . Ics) and ( ⁇ r_Est) and generate the synchronous reference frame currents (Iqse, Idse).
  • the motor 200 comprises a three-phase permanent-magnet synchronous motor (PMSM) ( 11 ) configured to receive the three-phase sinusoidal voltage commands (Vap . . . Vcp) and generate a motor output (Vn).
  • PMSM permanent-magnet synchronous motor
  • the voltage generator module 220 comprises a phase-to-neutral voltage generator ( 12 ), a summing junction ( 13 ), and a sampler module ( 14 ).
  • the phase-to-neutral voltage generator ( 12 ) can receive the three-phase sinusoidal voltage commands (Vap . . . Vcp) and the motor output (Vn) and can generate the machine phase voltages (Van . . . Vcn).
  • the summing junction ( 13 ) can receive the machine phase voltages (Van . . . Vcn) and generate the zero-sequence voltage (Vsn).
  • the sampler module ( 14 ) can receive the zero-sequence voltage (Vsn) and generate sampled three-phase zero-sequence voltages (VA_sn . . . VC_sn).
  • the output module 240 comprises a three-to-to converter module ( 15 ), an angle calculator module ( 16 ), an angle converter module ( 17 ), and an angle calibrator module ( 18 ).
  • the three-to-to converter module ( 15 ) can receive the sampled three-phase zero-sequence voltages (VA_sn . . . VC_sn) and generate two-phase zero-sequence voltages (VAlpha_sn).
  • the angle calculator module ( 16 ) can receive two-phase zero-sequence voltages (VAlpha_sn) and generate angle of the saturation induced saliency.
  • the angle converter module ( 17 ) can receive angle of the saturation induced saliency and generate rotor position angle ( ⁇ EstRaw).
  • the angle calibrator module ( 18 ) can receive rotor position angle ( ⁇ EstRaw) and generate the final estimated rotor position angle ( ⁇ r_est).
  • the current mapping module ( 1 ) is coupled to summer junctions ( 2 ) and ( 3 ), which are coupled to a current controller module ( 4 ) and receive the output of the stationary-to-synchronous conversion module ( 9 ).
  • Torque command (T* e ) is passed to torque to current mapping module ( 1 ) which generates the d and q axes current commands Idse* and Iqse* respectively. These current commands are added to the feedback measured current Idse and Iqse via the summer junctions ( 2 ) and ( 3 ) respectively.
  • the d and q-axes current error is fed to current controller module ( 4 ) which generates the d and q-axes voltage commands Vdse* and Vqse* respectively.
  • the output voltage commands are processed through synchronous to stationary conversion module ( 5 ) to generate three phase sinusoidal voltage commands Va*, Vb* and Vc*.
  • the synchronous-to-stationary conversion module ( 5 ) receives inputs from the current controller module ( 4 ) and the angle calibrator module ( 18 ), and generates outputs sent to the Space Vector PWM module ( 6 ).
  • the Space Vector PWM module ( 6 ) uses the output of the synchronous-to-stationary conversion module ( 5 ) to generate inputs for the multiplexer module ( 7 ) which also receives inputs from the injection vector generator module ( 10 ).
  • FIGS. 13-15 are a series of graphs showing synthesis of normal Space Vector PWM (SVPWM) waveform and injecting vectors.
  • SVPWM Space Vector PWM
  • the injecting vectors Sia, Sib and Sic
  • V 7 (1,1,1) the zero vector in the SVPWM waveforms.
  • the two complementary vectors V 1 -V 4 , V 3 -V 5 and V 5 -V 2 ) are injected sequentially to minimize the deviation of motor currents.
  • FIG. 13 is a graph showing injecting vectors (Sia, Sib and Sic) for zero sequence voltage measurement. These voltage commands are then converted to switching states (Sa, Sb and Sc) for phases A, B and C respectively via Space Vector PWM module ( 6 ).
  • FIG. 14 is a graph showing a normal Space Vector PWM (SVPWM) waveform for current control with switching states (Sa, Sb and Sc) for phases A, B and C, respectively.
  • SVPWM normal Space Vector PWM
  • the multiplexer module ( 7 ) generates inputs for the PWM inverter ( 8 ).
  • the multiplexer module ( 7 ) modifies these switching vectors with injection vectors Sia, Sib and Sic generated by module ( 10 ).
  • the modified switching vectors Sa′, Sb′ and Sc′ are then used to switch the IGBT switches in PWM inverter ( 8 ) to generate three phase sinusoidal voltage commands.
  • FIG. 15 is a graph showing a synthesized PWM waveform with modified switching vectors (Sa′, Sb′ and Sc′) used to switch IGBT switches in PWM inverter to generate three phase sinusoidal voltage commands.
  • the output generated by the PWM inverter ( 8 ) is supplied to the 3-phase permanent magnet synchronous motor ( 11 ) to generate the commanded torque Te* and to the phase-neutral voltage calculator module ( 12 ).
  • the resultant stator currents (Ias, Ibs and Ics) are sensed, sampled and passed to the stationary-to-synchronous conversion module ( 9 ).
  • the output of the stationary-to-synchronous conversion module ( 9 ) is synchronous reference frame currents (Iqs e and Ids e ) which are supplied to the summing junctions ( 2 ) and ( 3 ) to generate the current errors (Iqs e * and Ids e *).
  • Machine terminal phase voltages (Van, Vbn and Vcn) are measured with respect to the neutral point and supplied to the phase-neutral voltage calculator module ( 12 ).
  • the phase-neutral voltage calculator module ( 12 ) receives the output of both the PWM inverter ( 8 ) and the 3-phase permanent magnet synchronous motor ( 11 ), and uses these to generate phase to neutral voltages (V an , V bn , V cn ) which are provided to the summing junction ( 13 ).
  • the summing junction ( 13 ) combines the input signals (V an , V bn , V cn ) to generate a zero sequence voltage (V sn ).
  • the zero sequence voltage (V sn ) is supplied to zero sequence voltage sampling module ( 14 ).
  • the zero sequence voltage sampling module ( 14 ) samples the zero sequence voltages for each of the three phases to align the sample with the injected vector.
  • the zero sequence voltage sampling module ( 14 ) samples the zero sequence voltage (V sn ) according to injecting sequence, and generates three-phase zero sequence voltages (V A — sn , V B — sn , V C — sn ), which are supplied to a three phase-to-two phase conversion module ( 15 ) for three phase to two phase conversion.
  • the three phase-to-two phase conversion module ( 15 ) converts the three-phase zero sequence voltages (V A — sn , V B — sn , V C — sn ) to two-phase voltages (V Alpha — sn , V Beta — sn ), which are then passed through to the angle calculator module ( 16 ).
  • the output of module ( 16 ) is the angle of the saturation induced saliency which is of the twice the fundamental frequency.
  • the divider module ( 17 ) converts this signal to the rotor position angle by dividing with 2.
  • the estimated raw rotor position is passed to an angle calibrator module ( 18 ) to calculate the final estimated rotor position angle ⁇ r_Est.
  • the proposed sensorless algorithm of FIG. 12 was implemented and tested using a General Motors prototype traction control hardware which includes the motor controller and 50 kW axial flux wheel hub motor or SMPMM. The experimental results are shown in FIGS. 16-19 .
  • FIG. 16 is a graph showing three phase saturation induced (zero sequence voltage) signals at no load condition when no load torque is applied.
  • the experimental results shown in FIG. 16 illustrate strong zero sequence signals which can be used to deduce the rotor position. Thus, robust rotor position estimation is possible.
  • FIG. 17 is a graph showing three phase saturation induced (zero sequence voltage) signals at a 40% load condition when no load torque is applied.
  • SampDelay 9 uS
  • Te 200 Nm
  • the experimental results shown in FIG. 17 illustrate that even under loaded condition the zero sequence signal strength is maintained.
  • the test results under loaded condition exhibit additional harmonic contents which can be eliminated to estimate the second order harmonic (i.e., saturation induced saliency component) to estimate the rotor position.
  • the second order harmonic i.e., saturation induced saliency component
  • FIG. 18 is a graph showing measured and estimated rotor position angles with two phase saturation induced signals at no load condition when no load torque is applied.
  • FIG. 19 is a graph showing measured and estimated rotor position angles with two phase saturation induced signals at full load condition when 100% load torque is applied.
  • the experimental results shown in FIGS. 18 and 19 show that under no load and full load conditions the estimated rotor position signal exhibits excellent performance.
  • DSP digital signal processor
  • ASIC application specific integrated circuit
  • FPGA field programmable gate array
  • a general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine.
  • a processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
  • the word “exemplary” is used exclusively herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.
  • a software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
  • An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium.
  • the storage medium may be integral to the processor.
  • the processor and the storage medium may reside in an ASIC.
  • the ASIC may reside in a user terminal.
  • the processor and the storage medium may reside as discrete components in a user terminal.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Ac Motors In General (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
US11/300,525 2005-12-14 2005-12-14 Method and apparatus for sensorless position control of a permanent magnet synchronous motor (PMSM) drive system Expired - Fee Related US7525269B2 (en)

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EP06840217A EP1969710A2 (de) 2005-12-14 2006-12-13 Verfahren und vorrichtung zur sensorlosen positionssteuerung eines antriebssystems mit permanentmagnet-synchronmotor (pmsm)
PCT/US2006/061965 WO2007070814A2 (en) 2005-12-14 2006-12-13 Method and apparatus for sensorless position control of a permanent magnet synchronous motor (pmsm) drive system
CN2006800528567A CN101375491B (zh) 2005-12-14 2006-12-13 用于永磁同步电动机(pmsm)驱动系统的无传感器位置控制的方法和设备

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070290633A1 (en) * 2006-05-31 2007-12-20 Honda Motor Co., Ltd. Controller for motor and control method for motor
US20090160377A1 (en) * 2007-12-19 2009-06-25 Denso Corporation Control system for multiphase rotary machines
US20090273308A1 (en) * 2008-04-30 2009-11-05 Rockwell Automation Technologies, Inc. Position sensorless control of permanent magnet motor
US20100145519A1 (en) * 2008-12-10 2010-06-10 Hartmut Keyl Industrial robot and method to operate an industrial robot
US20100188033A1 (en) * 2008-09-23 2010-07-29 Aerovironment, Inc. Sensorless optimum torque control for high efficiency ironless permanent magnet machine
US20110018578A1 (en) * 2009-07-21 2011-01-27 Gm Global Technology Operations, Inc. Methods, systems and apparatus for detecting abnormal operation of an inverter sub-module
KR101172749B1 (ko) 2010-12-13 2012-08-14 한국전기연구원 교류 전원 장치의 출력 제어기
US20130033206A1 (en) * 2011-08-03 2013-02-07 GM Global Technology Operations LLC Methods, systems and apparatus for adjusting modulation index to improve linearity of phase voltage commands
US20130069568A1 (en) * 2011-09-15 2013-03-21 Curtiss-Wright Electro-Mechanical Corporation System and Method for Controlling a Permanent Magnet Motor
US8796978B2 (en) 2008-09-23 2014-08-05 Aerovironment, Inc. Predictive pulse width modulation for an open delta H-bridge driven high efficiency ironless permanent magnet machine
KR20200014785A (ko) * 2017-06-14 2020-02-11 로베르트 보쉬 게엠베하 Pwm 제어 인버터에 의해 공급되는 회전식 다상 전기 기계의 위상 전류들을 결정하는 방법
US10868485B2 (en) 2018-11-10 2020-12-15 Zhongshan Broad-Ocean Motor Co., Ltd. Constant torque control method for permanent magnet synchronous motor
US11171586B2 (en) 2019-04-25 2021-11-09 Black & Decker Inc. Low-speed sensorless brushless motor control in a power tool
US11374519B2 (en) 2019-06-10 2022-06-28 Black & Decker Inc. Field-oriented sensorless brushless motor control in a power tool
US12593746B2 (en) 2022-09-08 2026-04-07 Deere & Company Rotary mower blade position synchronization system

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB0422201D0 (en) * 2004-10-07 2004-11-03 Trw Ltd Motor drive control
JP4754417B2 (ja) * 2006-06-26 2011-08-24 本田技研工業株式会社 永久磁石型回転電機の制御装置
US8055399B2 (en) 2008-10-23 2011-11-08 Hydro-Gear Limited Partnership Control systems and methods for electric motors of utility vehicles
US8242721B2 (en) * 2008-10-31 2012-08-14 R&D Dynamics Corporation Position-sensorless control system and method of operation for a synchronous motor
IT1394426B1 (it) * 2009-06-05 2012-06-15 Reel S R L Unipersonale Metodo di controllo di un motore
US8253360B2 (en) * 2009-07-15 2012-08-28 GM Global Technology Operations LLC Vector controlled motor drive system implementing pulse width modulated (PWM) waveforms
US9007004B2 (en) 2009-11-06 2015-04-14 University Of Technology, Sydney Sensorless AC motor controller
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CN102237841B (zh) * 2011-04-08 2013-04-24 中国科学院微电子研究所 应用于永磁同步电机的无位置传感器位置估计的装置
DE102013205870B4 (de) * 2013-04-03 2025-01-02 Bayerische Motoren Werke Aktiengesellschaft Ansteuerverfahren für elektrische Maschine
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US10116243B2 (en) 2016-06-16 2018-10-30 Allegro Microsystems, Llc Determining motor position with complementary drive and detect and slight move
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US10181810B2 (en) 2016-06-16 2019-01-15 Allegro Microsystems, Llc Determining motor position with complementary driving and detection and current injection
CN107462807A (zh) * 2017-08-16 2017-12-12 济南大学 一种电动汽车永磁同步电机定子绕组故障诊断方法
US11005407B2 (en) * 2017-09-29 2021-05-11 Hitachi Industrial Equipment Systems Co., Ltd. Data obtaining method, inverter, and rotating electric machine
AT520570B1 (de) * 2017-11-03 2019-11-15 Dr Manfred Schroedl Verfahren zur Ermittlung der Rotorposition von synchron laufenden elektrischen Maschinen
US11575336B2 (en) * 2019-05-31 2023-02-07 Nxp Usa, Inc. Technique for on-the-fly start-up of a permanent magnet AC motor without a speed or position sensor
DE102019208497A1 (de) * 2019-06-12 2020-12-17 Robert Bosch Gmbh Verfahren zur Bestimmung einer Rotorlage einer elektrischen, rotierenden Maschine sowie eine elektrische, rotierende Maschine zur Durchführung eines solchen Verfahrens

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5585709A (en) * 1993-12-22 1996-12-17 Wisconsin Alumni Research Foundation Method and apparatus for transducerless position and velocity estimation in drives for AC machines

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6894450B2 (en) * 2002-01-16 2005-05-17 Ballard Power Systems Corporation Circuit configuration for permanent magnet synchronous motor control
US6703809B2 (en) * 2002-03-05 2004-03-09 Rockwell Automation Technologies, Inc. Flux position identifier using high frequency injection with the presence of a rich harmonic spectrum in a responding signal

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5585709A (en) * 1993-12-22 1996-12-17 Wisconsin Alumni Research Foundation Method and apparatus for transducerless position and velocity estimation in drives for AC machines

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US20090160377A1 (en) * 2007-12-19 2009-06-25 Denso Corporation Control system for multiphase rotary machines
US8179065B2 (en) * 2008-04-30 2012-05-15 Rockwell Automation Technologies, Inc. Position sensorless control of permanent magnet motor
US20090273308A1 (en) * 2008-04-30 2009-11-05 Rockwell Automation Technologies, Inc. Position sensorless control of permanent magnet motor
US20100188033A1 (en) * 2008-09-23 2010-07-29 Aerovironment, Inc. Sensorless optimum torque control for high efficiency ironless permanent magnet machine
US8796978B2 (en) 2008-09-23 2014-08-05 Aerovironment, Inc. Predictive pulse width modulation for an open delta H-bridge driven high efficiency ironless permanent magnet machine
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US20110018578A1 (en) * 2009-07-21 2011-01-27 Gm Global Technology Operations, Inc. Methods, systems and apparatus for detecting abnormal operation of an inverter sub-module
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US20070132415A1 (en) 2007-06-14
CN101375491A (zh) 2009-02-25
EP1969710A2 (de) 2008-09-17
WO2007070814A3 (en) 2008-07-17
WO2007070814A9 (en) 2008-06-05
WO2007070814A2 (en) 2007-06-21

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